Olivia Newton-John used ''medicinal cannabis'' to ease the pain of her breast cancer treatment.

The 68-year-old singer is currently battling cancer for the second time, and has now said she finds the drug - which is legal in the state of California - ''really important'' when it comes to easing the pain which comes alongside the aggressive cancer treatment, as well as promoting ''healing''.

Speaking to Australia's Daily Telegraph newspaper, the 'Grease' star said: ''I use medicinal cannabis, which is really important for pain and healing ... It's a plant that has been maligned for so long, and has so many abilities to heal. It's an important part of treatment, and it should be available. I use it for the pain and it's also a medicinal thing to do -- the research shows it's really helpful.''

Meanwhile, Olivia recently revealed she is ''feeling great'' since announcing her second cancer diagnosis earlier this year.

In a new video posted on behalf of the Olivia Newton-John Cancer Wellness and Research Centre, she said: ''Firstly, I'd like to express my gratitude to all of you who sent such kind and loving messages of support over the past few months. Your prayers and well wishes have truly helped me, and continued to lift my spirits. I'm feeling great and so look forward to seeing you soon!''

Olivia - who previously battled breast cancer in 1992 - was told her cancer had metastasised after suffering severe back pain earlier this year from what she thought was sciatica.

Doctors then informed her that her cancer had spread to the sacrum, which is the triangular bone in the lower back, situated between the two hip bones of the pelvis.

In a statement released in June, Olivia said she was ''totally confident'' that she would beat her cancer a second time, and hoped to ''inspire others'' with her success story.

She said: ''I am really grateful for and touched by the worldwide outpouring of love and concern. Thank you. I am feeling good and enjoying total support from my family and friends, along with a team of wellness and medical practitioners both here in the US and at my Olivia Newton-John Cancer Wellness and Research Centre in Melbourne, Australia. I'm totally confident that my new journey will have a positive success story to inspire others!''